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Anthropogenic Mass Extinction: The Science, the Ethics, and the Civics

Abstract and Keywords

We explore the science of mass extinction, link it to industrial civilization, use the concept of the banality of evil to explain the ethical situation, and then explain the various ways in which mass extinction poses further ethical problems within that situation, especially of environmental justice and the loss of value. Overall, humankind risks a profound failure of autonomy, perhaps our greatest achievement. For those who want to take action, we recommend the project of anthroponomy and large-unit/deep-branching conservation.

Keywords: mass extinction, industrialism, banality of evil, environmental justice, large-unit/deep-branching conservation, anthroponomy

1 Mass Extinction

One of the most striking features of the fossil record is how it registers the sudden and geographically widespread extermination of higher taxonomic groups, extinguishing effectively unrelated groups simultaneously. These are the so-called mass extinctions, a handful of biologically destructive events in the history of life that have been precipitated by environmental perturbations on a global scale.

The understanding of mass extinction as a distinctive phenomenon began to accumulate in the 1950s, accelerating with the 1980 discovery of a catastrophic impact event that killed the dinosaurs. We can now point to 18 mass extinction events in the fossil record (Bambach, 2006), five of which have seen the number of species on Earth reduced by 75% or more.

The last of these “Big Five” mass extinction events took place 65 million years ago (mya) at the end of the Cretaceous period. The dominant opinion is that a meteorite more than 6 miles (10km) in diameter struck the Yucatan peninsula and set off a chain reaction that would eventually drive the dinosaurs and 76% of all species then living to extinction. However, none of the other Big Five mass extinctions can be directly linked to rocks from the sky, and paleontologists generally agree that extraterrestrial causes are not necessary to produce the level of destruction witnessed at the end of the Cretaceous. Indeed, the primary cause of the end-Permian extinction (~251 mya)—which left only 4% of species alive—is currently thought to have been a series of effusive volcanic eruptions that took place in Siberia over about one million years (Erwin, 2006, chapter 2).

How do mass extinction events work, and how do they differ from “background” times in which extinction still occurs regularly but not on the scale that characterizes these events? There is no consensus for any of the Big Five as to what factors triggered the sharp acceleration in extinctions (even the Cretaceous impact hypothesis has its skeptics (e.g., Keller, (p. 428) 2008), but there is wide agreement that the unique form and scale of extinction seen during mass extinctions is of a special kind.

One feature of that kind is the extinction of widespread species (Raup, 1991: 182). Call this the widespread extinction criterion. Ecological and paleontological evidence both suggest that the extinction of a species with a large geographic range is a biologically rare event—indeed, ecologist Daniel Simberloff has called species that are widespread “effectively immortal” (Simberloff, 1994: 165). Normally, a genus composed of widespread species will long outlive one composed of a more range-restricted species. But not during mass extinctions. Having widespread species at in the end-Cretaceous did not prolong a genus’s life (Jablonski, 1986).

Another feature of mass extinction is the sheer magnitude of species extinctions. Call this the magnitude criterion. Raup (1991) produces a “kill curve” for Phanerozoic marine life, showing how often an extinction event of a given magnitude comes around. On average, there has been an extinction event every million years in which roughly 5% of species are wiped out. In contemporary terms, that would be like 100,000 of the named, extant species going extinct in a single event. But that would be mild by comparison to even the smallest clearly identifiable of the Big Five mass extinctions, the Pliocene event. The time between truly epic mass extinctions, like the end-Cretaceous extinction, is upward of 100 million years. Something like the end-Permian extinction can be expected to happen just once every several billion years (Raup, 1991: 44). These numbers suggest that the circumstances required to produce the number of species deaths suffered during the Big Five mass extinctions are not something the Earth has an easy time generating.

The third and last feature is the peculiar form of extinction that we find only during mass extinctions, which typically see the simultaneous extinction of many ecologically dissimilar and effectively unrelated higher taxonomic groups: genera (sets of species), families (sets of genera), and orders (sets of families).1 Call this the dissimilar groups criterion. In the general case, we know that the odds of chopping off an entire branch of the evolutionary tree are very low unless the species on that branch are very similar ecologically (Green et al., 2011). We also know that the odds of ecological similarity are lower if species are unrelated. Since extinguishing a higher-level taxonomic group (which would be more deeply branched according to the tree metaphor) means extinguishing every member of every species in that group, we know that the extinction of a higher-level/more deeply branching group is a very special event. Yet each of these is part of the standard mass extinction. The impact that killed over 1,000 dinosaur genera also killed 60% of calcareous sponge genera—two groups that have separated by almost a billion years of evolutionary history with nothing in common ecologically (Bambach, 2006: 140). It is important to appreciate how difficult this is to do. As Raup (1991: 183) observes, “Even extinction mechanisms that cause the collapse of a whole ecosystem rarely affect more than one basic habitat.” By contrast, the sort of perturbations required to extinguish groups as phylogenetically and ecologically distinct as sponges and dinosaurs in a single event disrupt very different ecologies and very distant ecosystems.

Each one of these phenomena—extinction of geographically widespread species, extinction of very high numbers of species, and extinction of phylogenetically and ecologically distinct higher taxonomic groups—is a low-probability event. The fact that all three are routine features of mass extinction events should give the reader a sense not only of the extreme improbability of generating these types of events, but also of the breadth and magnitude of the catastrophe required to do so. This is particularly true of the Big Five. Only five times in (p. 429) the last 540 million years has life on Earth been so difficult that >75% of species went extinct. During the end-Permian, a Siberian region roughly the size of Mexico had to be covered in lava nearly a mile thick in some places to make the atmosphere inhospitable enough to extinguish some 95% of species (Erwin, 2006, chapter 2). In the end-Cretaceous event, a meteor the size of a city had to crash to Earth. Generally speaking, it takes something historically unprecedented or extremely violent to achieve the extinction rates that characterize these events. But in the case of the end-Permian extinction event, a million-year ooze of lava sufficed: Earth’s ecology was not prepared for it.

Are we today at the outer edge of a mass extinction event caused by homo sapiens’ population growth and industrial economy, with all the effects that these two stressors on habitat and the climate involve? One difficulty involved in answering this question concerns the historical formation of the scientific discourse around mass extinctions, which evolved alongside paleontology as one of the discourses that brought paleontology into its own as a discipline. Technically, a mass extinction—understood as a paleontological concept—depends on an evidentiary basis in the fossil record of durably skeletonized marine invertebrate genera. This means that other indicators of elevated extinction rates are normally not considered relevant to the determination of a mass extinction (cf. Barnosky et al. 2011). But the fossil record of our time is still in the process of sedimenting. We do not have it yet. Given that we cannot know the fossil record of durably skeletonized marine invertebrate genera for our present time, we seem to have no short-term, immanent method for judging whether we are entering an anthropogenic mass extinction.

1.1 Industrialism

Be that as it may, the current rates of extinction among other forms of life are alarming enough to suggest to many scientists that we are uncomfortably close to entering a new mass extinction event. Gorke (2003) lists a number of causes of anthropogenic elevated extinction, which he appears to link generally to humankind, but the main cause is habitat destruction from a variety of causes related to the deadly intersection of (a) human population growth with (b) an extractive and polluting economy. Both (a) and (b) are the result of the massive, technological potential of modern industrial economies—here, no fundamental difference between capitalism and the late, state-centric communism are noticeable (Jonas, 1984). Earlier technology (e.g., weapons for killing at a distance some 11,000 years ago or agriculture beginning at the dawn of recorded human history) contributed to elevating extinction rates on Earth. But nothing has made mass extinction more likely than the unintended effects of the industrial age, now expanded globally in the age of information through a system of extractive, polluting, corporate, capitalist production (Castells, 1996).

It is important to embed the ethical considerations we address within this social framework, a framework we call for short industrialism. Societies that resist or minimize (with difficulty) their relation to mass-scale, industrial extraction and pollution are not to blame for contributing to the risk of mass extinction. At the same time, any society that benefits from such an economy, growing in population exponentially for instance, is still part of the dynamic contributing to mass extinction and in that sense is still to blame. We should also realize that most nations of the globe contribute in some way to global, industrial economy. (p. 430) Today, we are faced with a global economy that, by being collectively mismanaged and by misconstruing its ethical relation to life on Earth and to future human beings is prospering in the present while risking a mass extinction in the future. Gardiner (2011) calls this “front-loading.” Until we manage to change the form of economy that currently manifests our industrial mismanagement—changing, too, the short time scales, lack of collective action, abstract form of value, and other related structural and conceptual problems of corporate capitalism in the context of actual Earth ecologies—we will continue headlong into a mass extinction (Bendik-Keymer, 2012). The ethical reasoning this handbook offers should be used to explain why changing our political economic form on a planetary scale is so important.

1.2 Autodestruction

When a mass extinction takes place, the ecosystems that enable the current round of life on Earth disintegrate as food chains collapse. The systems of life enabling civilization change. Houses of cards fall down. The planetary disintegration of the ecosystems enabling life as we know it undermines what we might call the standard conditions for human life, and the question is whether the result of this undermining also undermines a safe operating space for humankind (Rocktröm et al., 2009). Some paleontologists think that it would, while other scientists who work on the issue think (1) that we know too little of how the extinction would unravel the current age of life on Earth and (2) that human technological capacity is remarkably quick to develop. Nonetheless, the range is dire—from the mass extinction involving an extinction event for homo sapiens to the mass extinction involving a serious undermining of the carrying capacity of the ecosystems on which we have historically depended. All this leaves to the side, as well, the status of non-human species, which many have value on their own (Rolston III, 2012).

A number of issues arise around the threat of mass extinction that are addressed elsewhere in this handbook.

  1. 1. The conditions of agency. Seemingly many necessary conditions of human agency are threatened by the cascade into a mass extinction and mutadis mutandis by an elevated extinction event as it becomes more and more severe. We need only to consider threats to food supplies and the ecosystem services on which we depend to imagine this (cf. Holland, 2012). The process leading to a mass extinction involves the elimination of biological families and orders, some of which can be crucial to human life as we know it. The wealthy may be able to survive, but the global poor (who exist within highly developed nations as well as in underdeveloped ones) may find themselves increasingly hard pressed to find food, materials for living, and to continue many traditional ways of life. The flourishing of the global poor is likely to be challenged in many ways, and this even more given intensified competition and violence over dwindling resources. Insofar as there are ethical issues arising from a threat to health, happiness, human development, or the ability to exercise substantive freedoms, anthropogenic mass extinction and even elevated extinction events raise them (cf. Nussbaum, 2011). Accordingly, the environmental threats to human agency discussed in many other places in this handbook should be brought to bear on (p. 431) any discussion of the ethics surrounding anthropogenic mass extinction, with a clear sense of the scale and irreversibility of the extinction event in mind.

  2. 2. Cultural value. In so far as there are ethical questions around the cultural (including aesthetic or religious) value of biological and even geological nature, anthropogenic mass extinction matters. Periods of mass extinction effectively reshape the biosphere which, being in concert with Earth’s geology, affects the geosphere as well. In so far as people hold parts of either the biosphere or geosphere to be valuable for aesthetic or cultural reasons, anthropogenic mass extinctions threatens much of value. Remember how Leopold (1948) noticed that culling wolves led to the erosion of topsoil when uncontrolled elk ate away trees whose roots held the soil firm? Imagine this kind of dynamic on a massively larger scale. Accordingly, one should apply the axiological concerns addressed elsewhere in this handbook to anthropogenic mass extinction, keeping in mind as always the scale and irreversibility of mass extinction.

  3. 3. Environmental justice. Insofar as any of the matters of agency or of cultural value are also concerns of justice, anthropogenic mass extinction raises significant questions of justice. Problems of intergenerational justice or of global justice resulting from a global environmental problem that is itself caused by our contemporary industrial economy apply to anthropogenic mass extinction. If we industrial humans cause a mass extinction, we affect people globally and, irreversibly, into the rest of the future of humankind. This effect is categorically different in the case of mass extinction than in the case of making individual, valuable species go extinct. Mass extinction produces ecological chaos. This is an effect of a different kind than the loss of individually valuable species, although their loss can also involve issues of justice. Accordingly, the discussions relating to these issues of justice discussed elsewhere in this handbook should be consulted when considering the ethics of anthropogenic mass extinction. Mass extinction is an amplifier of many kinds of environmental problems and is itself a severe matter of justice: what right have we industrial beneficiaries to enjoy an Earth that can easily support us when our actions going forward risk an Earth whose ecosystems have disintegrated on a planetary scale?

  4. 4. The moral corruption of techno-optimism. Will technology provide us with the silver bullet to overcome a trophic level cascade into mass extinction? The promise of a technological solution that will be able to stop mass extinction raises speculative questions that are addressed under the current technological fix of climate change by geoengineering. Even more so than with geoengineering currently, reversing a trophic level collapse at a global scale is mere science fiction at present. We would be morally corrupt to expect it.

Autodestruction.

The four previous issues are common in environmental ethics. But not the most extreme case that attends the threat of mass extinction: anthropogenic mass extinction risks the unintended destruction of the human species. Clearly, there are ways some form of technology could kill the human species—for example, nuclear holocaust or bioengineered pandemic. But of the major environmental issues discussed in this handbook, perhaps only mass extinction involves the plausible risk of killing our kind and this due not to a bomb or a virus but to the grinding, massive operations of a form of economy and of society—something entirely banal. What is at stake ethically in killing ourselves as a species due to a banal social form?

(p. 432) The first question we have to face is whether there is anything ethically specific involved in putting an end to humankind, that is, our life form, above and beyond the wrongs that may be involved in the death of each individual. We are searching for whether there is an order of wrong that shifts in scale and focus to the level of the species (cf. Sandler, 2012). Would human species autodestruction shift the kind of wrong akin to the shift when we move from, for example, interpersonal crimes to crimes against humanity? Human species autodestruction would appear to be a wrong in its own category. The wrong is the wrong of putting an end to humankind and all that is of value in it. This is a cataclysmic wrong. It is a wrong at the level of the whole, not concerning individuals. Much work could be done to conceptualize and specify the logic of this kind of wrong in the context of mass extinction studies (cf. Hatley, 2012).

2 The Banality of Evil

Whereas moving headlong into an elevated extinction event with the prospect of increasing the magnitude, range, and taxonomic reach of the extinction we cause is most disturbing when one speculates as an alarmist about human species autodestruction, moving headlong into our elevated extinction event is the most morally objectionable when one considers what it shows about our global economy. Our current global order appears as immoral when one considers it as leading plausibly to the edge of a mass extinction. Neiman (2002) understands evil as whatever threatens the sense of human life as a whole. To be evil, a form of society—including what it permits and pursues economically—must threaten the sense of human life as a whole. Threatening anthropogenic mass extinction does this.

It destroys the conditions of sense.

First, an anthropogenic mass extinction would undermine the sense we make of human life by risking human species autodestruction unintentionally. There can be no sense of human life if there is no human life.

It destroys the backgrounds, sites, and objects of sense.

Second, anthropogenic mass extinction would undermine all the ongoing meaning (including the valuable meaning) associated with the species and ecologies that are extinguished or collapse during a mass extinction event. As discussed above, mass extinction events reshape the entire biological fabric of the Earth and bear on many geological processes as well. The current system of life changes. Mass extinction events result in an unfamiliar Earth. This is sense-undermining, and it would be all the more so in that we have unintentionally caused it while trying to live a life that makes sense in the world. It is important to note, too, that many—in our view legitimate—concerns about the intrinsic value of non-human nature reside here as well; for the bearers of intrinsic value extinguished in a mass extinction would take much meaning with them. We would lose so many life forms that are good in themselves. Moreover, any ongoing meaning that is associated with how we should relate to such intrinsically valuable life forms would disappear also. All we would have would be historical memory—a ghost story and its shadow. So much ritual, literature, and music and so many family albums would become dead forms, dusty memories. If it is callous, thoughtless, unkind, violent, wanton, or selfish of us to extinguish intrinsically valuable life, then anthropogenic mass extinction would also undermine the meaning of our (p. 433) character, showing us to be callous, thoughtless, unkind, violent, wanton, or selfish toward them and toward ourselves. Even self-hatred cannot produce such deracinating effects.

It destroys the sense of ourselves.

Third, anthropogenic mass extinction would contradict any view of ourselves as relatively benign. If original sin has become a special metaphysical belief of only some religious believers, anthropogenic mass extinction raises the specter of our society being unintentionally but characteristically destructive. Our immoral flaw would then not reside in being human but in remaining passive to the lack of social regulation needed to produce a postindustrial global economy based on stable human population and renewable energy and products (the technosphere not extracting from the biosphere; Braungart and McDonough, 2002). It would reside in our failing to be active citizens who find a way to self-regulate on enough scales to keep ourselves globally within justifiable norms (cf. Scruton, 2012). The destruction most of us cause is senseless destruction in that we unintentionally do it by way of remaining docilely complicit in our existing system of production and waste and in our dominant unrestrained view of population growth, with little or no awareness, with no good justification, and with many ethical problems produced as a result, possibly including our own extinction. Such characteristic, senseless destruction undermines the sense of human life by introducing societal level doubt and overwhelming the capacities of individual human agents (cf. Gardiner, 2011).

The threefold evil we risk causing—of our own extinction, of destroying much of value in the bio- and geospheres, and of our society’s characteristic destructiveness—is banal (Arendt, 2006). Evil is banal if and only if it arises, not from ill intentions or even obvious individual flaws but from everyday, seemingly acceptable social organization. Accordingly, banal evil is superficial, not demonic or deep. It arises from a social or institutional system, not an individual. The system of behavior that constitutes it appears familiar, acceptable, or even common sense. The things that go into making a banal evil can be trivial for an individual or even a locality. They can appear as routine duties for a functionary. On this formulation, environmental problems such as running headlong—business as usual—into a more and more widespread, massive, and taxonomically wide-reaching extinction event display the banality of evil. And we—certainly not as depersonalized as Adolf Eichmann—display how ordinary complicity in that evil can be. What the (not unreasonably) speculative risk of anthropogenic mass extinction shows us is that we have a civilizational disorder and that each of us in it who remain complicit within it suffer for want of a sound conscience (Bendik-Keymer, 2010).

3 Anthroponomy

Faced with this diagnosis, one clear response is for us to learn to act collectively on a number of scales so as to be able to shape local, regional, and national government in such a way that we internalize responsibility for our unintentional consequences and deepen the sense of human life. This is a civic task. Anthropogenic mass extinction, like many planetary environmental problems, presents us with problems in science, in conservation, in ethics, and ultimately in politics. One of the merits of considering it is to underline the task of anthroponomy.

(p. 434) Anthroponomy is a civic task demanding the construction of institutions—market, public, and civil societal—on a number of scales that can collectively reform our global economy so that humankind as an aggregate collective lives up to what basic humanity demands. For starters, this would be the maintenance of a world that makes sense to us, that does not become evil. Anthroponomy is the big game in town when it comes to dealing with mass extinction, as well as with other planetary scale environmental changes such as climate change and ocean acidification. No serious environmentalist or scholar of environmentalism can neglect it. To deemphasize it is to give up on the only realistic long-term solution to contemporary environmental problems.

Our first ethical priority as people concerned with the risk of anthropogenic mass extinction must accordingly be political: to demand political, market, and civic societal institutions on a number of scales, from the local to the national, and involving international networks of governance that are collectively capable of regulating our economy eventually on a planetary scale, even if the primary site of regulation is local, regional, or national (cf. Scruton, 2012; Brenner, 2013). Given the driving cause of the risk of anthropogenic mass extinction, anthroponomy will have to be anchored in an economic form beyond the communism and corporate capitalism of the modern age, toward a postindustrial civilization (Jonas, 1984, Braungart and McDonough, 2002). This multiscaled, multisited anthroponomy rooted in a network of norm-bearing institutions will have to address many risk factors causing our current elevated extinction event: overpopulation, ecologically destabilizing pollution, human settlement sprawl and widespread habitat destruction (cf. Davis, 2007), and the big problems of climate change and ocean acidification—basically any problems straining our planetary boundaries (Rockström et al., 2009). In addition, none of these institutions will be ultimately viable until we arrive at an effective international order, the precursor to any possible global governance (not government). Accordingly, citizens concerned with anthropogenic mass extinction should focus on conservation, certainly; support scientific advances in extinction studies as well; but not let any of these overshadow the essentially political-economic task of anthroponomy. Local governance appears to be the most effective form on the planet for fostering accountability and maintaining self-governance, that is, for keeping us as a collective within norms that make sense and do not undermine sense (Scruton, 2012). A very basic challenge of anthroponomy therefore appears in how we will link the local scale to international governance, which is to this day essentially idealistic and unstable. It may be in intensified work on our nation states, and it may also be through transnational networks of governance, be they economic or appearing in the realm of affiliation-specific, transnational civil society—as in the case of Rotary Clubs, conservation societies, or activist networks against unaccountable multinational corporations.

4 Large-Unit / Deep Branching Conservation

If today’s accelerating extinction rates were to be part of a mass extinction event, we can look forward to the same sort of fundamental reorganization of the biosphere that took place during previous mass extinctions. Mass extinctions, in Jablonski’s (2001: 5397) words, “remove successful incumbents,” fundamentally altering the adaptive success of existing evolutionary (p. 435) strategies and demolishing the evolutionary status quo. Before the K-Pg mass extinction, mammals were an unimpressive lineage composed of small things eating even smaller things (bugs, worms, baby dinosaurs; Hu et al., 2005). By the end of the recovery period (~ 5 my), they were well on their way to being the dominant form of terrestrial life. Mass extinctions reorganize the system of the biosphere, with no guarantee that currently successful taxa—like us—will be part of the new order on Earth.

If we’re ultimately concerned with preserving the ecological relationships that currently characterize life on Earth, then the threat of mass extinction compels us to revise our thinking about what constitutes meaningful conservation biology. We need to consider mitigation of the elevated extinction rate event we’re in with an eye to keeping it as far as we can from becoming a mass extinction. We’ve known for at least a generation that practical constraints (e.g., on our knowledge, on our resources) mean that we will have to prioritize when it comes to what we decide to save (cf. Sandler, 2012). But the threat of mass extinction adds a new dimension to the prioritization process. The destabilization caused by mass extinctions stems from the destruction of higher-order/deeper branching biological entities that is a unique and characteristic part of the mass extinction process. If preserving the current form of ecological stability matters to us, then that suggests a shift in the sort of biological entities that qualify as having ethical significance. On the scale of mass extinction, saving particular, individual species no longer seems as important. If the stability of the biosphere itself is in question, then the biological entities that seem to matter are the ones that can preserve that stability—for example, ecosystems, large-scale communities, geographic regions that generate much of the planet’s biodiversity (so-called “biodiversity hotspots”). As to individual species, those preserving deep branching lineages would seem more important (Pinet et al., 2013). But if the biosphere’s general stability depends on the stability of those large-scale biological units, and if the stability of those units is independent of their particular constituents, then our efforts should focus on those larger-scale units, since they make a difference to general stability.

Of course it’s not news to most readers that preserving ecosystems and communities is important. But the independence of these entities from their current inhabitants may not be common knowledge, and it has significant ethical implications for how we ought to organize our conservation efforts. To take one example, large-scale biological communities are thought to be composed of a random draw from the regional species pool. From the perspective of the community’s persistence, the collection of species that composes it at any given time is not especially significant. Individual species will come and go as time passes, but the community will remain unperturbed. If that’s true, it’s not clear that we have an ethical imperative to focus conservation efforts on any of the incumbent species of a given community, even if our primary concern is the preservation of the community of which they are a part. Rather, what we ought to be ensuring is that the regional species pool has sufficient reserves to reconstitute that community, along either functional or structural dimensions.

The point of this example is not to recommend a specific conservation strategy, but rather to emphasize the more important fact that mass extinctions threaten levels of the biological hierarchy that are much higher up and more deeply branching than we’re accustomed to thinking about in ethical terms. We need to retrain our moral sense (and our scientific research priorities) to reflect the biological facts that are significant for the preservation of the life as we know it. Should a new mass extinction be occurring, the complex dynamics of it will very likely undermine conservation efforts aimed at particular species. But thinking (p. 436) toward the kind of things that happen in a mass extinction can guide us toward mitigating the elevated extinction rate event that is occurring so that we resist falling into a mass extinction while our efforts at anthroponomy lag behind. Perhaps an anthroponomic test for the moment is to see how well we can support regional conservation of large-scale biological units, even transnational ones.

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                                                                Notes:

                                                                (1.) For example, dogs belong to the genus canis, in the family Canidae, which is part of the order Carnivora, a group that also contains walruses.